package day07;

import java.util.Random;

/**
 * 需求：生成？位验证码(大写字母，小写字母，数字)
 */
public class VerificationCode {
    public static void main(String[] args) {
      String code=generateVeriCode(6);
        System.out.println("验证码是："+code);


    }
    public static String generateVeriCode(int len){
        String code ="";
        char[] chs={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q',
                'r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I',
                'J','K', 'L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','0',
                '1','2','3','4','5','6', '7', '8','9'};
        for (int i = 1; i <=len; i++) {
            Random rand=new Random();
            int index= rand.nextInt(chs.length);
            //int index=(int)(Math.random()*chs.length);//随机下标
            code+=chs[index];//获取随机下标拼接到code中
        }

        return code;

    }



}
